:root {
  --orange: #FF7A45;
  --orange-light: #FF9A6B;
  --orange-deep: #E85D2A;
  --orange-soft: #FFD8A8;
  --green: #2E8B57;
  --bg: #FFF8F3;
  --bg-alt: #FFFFFF;
  --bg-soft: #FFF1E8;
  --text: #2B2320;
  --text-soft: #6B5E57;
  --text-muted: #9C8B82;
  --border: rgba(255, 122, 69, 0.16);
  --glass-bg: rgba(255, 255, 255, 0.62);
  --glass-border: rgba(255, 255, 255, 0.75);
  --shadow-sm: 0 2px 8px rgba(232, 93, 42, 0.08);
  --shadow-md: 0 8px 28px rgba(232, 93, 42, 0.12);
  --shadow-lg: 0 18px 48px rgba(232, 93, 42, 0.18);
  --radius-sm: 10px;
  --radius-md: 18px;
  --radius-lg: 28px;
  --radius-pill: 999px;
  --grad-hero: linear-gradient(135deg, #FFB088 0%, #FF7A45 42%, #FF5E8A 100%);
  --grad-accent: linear-gradient(120deg, #FF7A45 0%, #FFB347 100%);
  --grad-soft: linear-gradient(160deg, #FFF8F3 0%, #FFEFE4 100%);
  --font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", sans-serif;
  --maxw: 1180px;
  --transition: 0.32s cubic-bezier(0.22, 0.61, 0.36, 1);
}

body.dark {
  --orange: #FF8A5C;
  --orange-light: #FFA57E;
  --orange-deep: #FF6A34;
  --orange-soft: #5A3B2C;
  --green: #4FBF83;
  --bg: #17120F;
  --bg-alt: #1F1915;
  --bg-soft: #241C17;
  --text: #F4ECE6;
  --text-soft: #C9BAB1;
  --text-muted: #93837A;
  --border: rgba(255, 138, 92, 0.2);
  --glass-bg: rgba(36, 28, 23, 0.6);
  --glass-border: rgba(255, 255, 255, 0.08);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 8px 28px rgba(0, 0, 0, 0.45);
  --shadow-lg: 0 18px 48px rgba(0, 0, 0, 0.55);
  --grad-hero: linear-gradient(135deg, #4A2A1D 0%, #6E2F1F 45%, #7A2A44 100%);
  --grad-soft: linear-gradient(160deg, #1F1915 0%, #241C17 100%);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.75;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  transition: background var(--transition), color var(--transition);
  overflow-x: hidden;
}

img,
svg {
  max-width: 100%;
  display: block;
}

a {
  color: var(--orange-deep);
  text-decoration: none;
  transition: color var(--transition), opacity var(--transition);
}

a:hover,
a:focus-visible {
  color: var(--orange);
  text-decoration: underline;
  text-underline-offset: 3px;
}

h1, h2, h3, h4 {
  line-height: 1.35;
  margin: 0 0 0.6em;
  color: var(--text);
  font-weight: 800;
  letter-spacing: -0.01em;
}

h1 { font-size: clamp(1.7rem, 4.4vw, 2.9rem); }
h2 { font-size: clamp(1.35rem, 3vw, 2rem); }
h3 { font-size: clamp(1.1rem, 2.2vw, 1.35rem); }

p { margin: 0 0 1em; color: var(--text-soft); }

ul, ol { margin: 0 0 1em; padding-left: 1.3em; color: var(--text-soft); }
li { margin-bottom: 0.4em; }

blockquote {
  margin: 0 0 1em;
  padding: 1em 1.2em;
  border-left: 4px solid var(--orange);
  background: var(--glass-bg);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

blockquote p { margin: 0; color: var(--text); font-style: italic; }

address { font-style: normal; }

time { color: var(--text-muted); font-size: 0.85rem; }

.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

/* ============ 通用按钮 ============ */
.btn,
#site-search button,
#theme-toggle,
#menu-toggle,
#back-to-top,
.slider-controls button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4em;
  font-family: inherit;
  font-size: 0.92rem;
  font-weight: 700;
  padding: 0.62em 1.4em;
  border: none;
  border-radius: var(--radius-pill);
  cursor: pointer;
  color: #fff;
  background: var(--grad-accent);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition), background var(--transition), color var(--transition), filter var(--transition);
}

.btn:hover,
#site-search button:hover,
#theme-toggle:hover,
#menu-toggle:hover,
#back-to-top:hover,
.slider-controls button:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  filter: brightness(1.05);
  text-decoration: none;
  color: #fff;
}

.btn:active,
button:active { transform: translateY(0) scale(0.98); }

.btn:focus-visible,
button:focus-visible,
a:focus-visible,
input:focus-visible,
summary:focus-visible {
  outline: 3px solid var(--orange);
  outline-offset: 3px;
}

/* ============ Header ============ */
#site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--glass-bg);
  backdrop-filter: blur(18px) saturate(160%);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
  border-bottom: 1px solid var(--glass-border);
  transition: box-shadow var(--transition), background var(--transition);
}

#site-header.sticky {
  box-shadow: var(--shadow-md);
  background: var(--glass-bg);
}

.header-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0.7rem 1.2rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-weight: 900;
  font-size: 1.15rem;
  color: var(--text);
  letter-spacing: 0.02em;
}

.brand:hover { color: var(--orange); text-decoration: none; }

.brand svg {
  transition: transform var(--transition);
  filter: drop-shadow(0 3px 6px rgba(232, 93, 42, 0.3));
}

.brand:hover svg { transform: rotate(-8deg) scale(1.06); }

.brand-name {
  background: var(--grad-accent);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

#main-nav { flex: 1 1 auto; }

#main-nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.15rem;
}

#main-nav li { margin: 0; }

#main-nav a {
  display: block;
  padding: 0.4em 0.7em;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-soft);
  border-radius: var(--radius-pill);
  transition: color var(--transition), background var(--transition);
}

#main-nav a:hover,
#main-nav a:focus-visible {
  color: var(--orange-deep);
  background: rgba(255, 122, 69, 0.1);
  text-decoration: none;
}

.header-tools {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

#site-search {
  display: flex;
  align-items: center;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  overflow: hidden;
  transition: box-shadow var(--transition), border-color var(--transition);
}

#site-search:focus-within {
  border-color: var(--orange);
  box-shadow: 0 0 0 4px rgba(255, 122, 69, 0.14);
}

#site-search input {
  border: none;
  background: transparent;
  padding: 0.5em 0.9em;
  font-family: inherit;
  font-size: 0.88rem;
  color: var(--text);
  width: 152px;
  outline: none;
}

#site-search input::placeholder { color: var(--text-muted); }

#site-search button {
  border-radius: 0;
  padding: 0.5em 1em;
  box-shadow: none;
}

#theme-toggle,
#menu-toggle {
  background: var(--bg-alt);
  color: var(--text-soft);
  border: 1px solid var(--border);
  box-shadow: none;
  padding: 0.5em 1em;
  font-size: 0.85rem;
}

#theme-toggle:hover,
#menu-toggle:hover {
  color: var(--orange-deep);
  background: rgba(255, 122, 69, 0.1);
  box-shadow: none;
}

#menu-toggle { display: none; }

/* ============ Hero ============ */
#hero {
  position: relative;
  background: var(--grad-hero);
  padding: 3rem 1.2rem 2rem;
  overflow: hidden;
}

#hero::before,
#hero::after {
  content: "";
  position: absolute;
  border-radius: 50%;
  pointer-events: none;
  filter: blur(2px);
}

#hero::before {
  width: 420px; height: 420px;
  top: -160px; right: -120px;
  background: radial-gradient(circle, rgba(255, 216, 168, 0.55), transparent 68%);
}

#hero::after {
  width: 340px; height: 340px;
  bottom: -140px; left: -100px;
  background: radial-gradient(circle, rgba(255, 94, 138, 0.4), transparent 70%);
}

.hero-slider {
  position: relative;
  max-width: var(--maxw);
  margin: 0 auto;
  min-height: 260px;
  z-index: 1;
}

.slide {
  display: none;
  padding: 1.6rem 1.8rem;
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.16);
  border: 1px solid rgba(255, 255, 255, 0.32);
  backdrop-filter: blur(16px) saturate(150%);
  -webkit-backdrop-filter: blur(16px) saturate(150%);
  box-shadow: 0 16px 40px rgba(120, 40, 10, 0.22);
  animation: slideIn 0.6s cubic-bezier(0.22, 0.61, 0.36, 1) both;
}

.slide.active { display: block; }

.slide h1,
.slide h2 {
  color: #fff;
  text-shadow: 0 2px 10px rgba(120, 40, 10, 0.28);
}

.slide p {
  color: rgba(255, 255, 255, 0.94);
  max-width: 72ch;
  margin-bottom: 1.1rem;
}

.slide .btn {
  background: #fff;
  color: var(--orange-deep);
  box-shadow: 0 8px 22px rgba(120, 40, 10, 0.25);
}

.slide .btn:hover { color: var(--orange-deep); }

@keyframes slideIn {
  from { opacity: 0; transform: translateY(18px); }
  to { opacity: 1; transform: translateY(0); }
}

.slider-controls {
  display: flex;
  gap: 0.6rem;
  margin-top: 1rem;
  justify-content: flex-end;
}

.slider-controls button {
  background: rgba(255, 255, 255, 0.22);
  border: 1px solid rgba(255, 255, 255, 0.4);
  color: #fff;
  font-size: 0.82rem;
  padding: 0.45em 1.1em;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.breadcrumb {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 1.2rem auto 0;
  padding: 0;
  max-width: var(--maxw);
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.85);
  position: relative;
  z-index: 1;
}

.breadcrumb li { margin: 0; }

.breadcrumb li + li::before {
  content: "/";
  margin-right: 0.4rem;
  opacity: 0.6;
}

.breadcrumb a { color: #fff; }
.breadcrumb a:hover { color: #FFE3C7; }

/* ============ Sections 通用 ============ */
main > section {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 3rem 1.2rem;
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.7s ease, transform 0.7s cubic-bezier(0.22, 0.61, 0.36, 1);
}

main > section.revealed {
  opacity: 1;
  transform: translateY(0);
}

#hero,
#stats { opacity: 1; transform: none; }

#hero { max-width: none; padding-left: 0; padding-right: 0; }

main > section > h2 {
  position: relative;
  display: inline-block;
  padding-bottom: 0.45rem;
  margin-bottom: 1.6rem;
}

main > section > h2::after {
  content: "";
  position: absolute;
  left: 0; bottom: 0;
  width: 56px; height: 4px;
  border-radius: var(--radius-pill);
  background: var(--grad-accent);
}

/* ============ Stats ============ */
#stats {
  max-width: var(--maxw);
  margin: -2rem auto 0;
  padding: 0 1.2rem 2rem;
  position: relative;
  z-index: 2;
}

#stats h2 {
  font-size: 0.95rem;
  color: var(--text-muted);
  font-weight: 600;
  margin-bottom: 1rem;
  letter-spacing: 0.08em;
}

.stats-list {
  list-style: none;
  margin: 0;
  padding: 1.4rem 1.2rem;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(18px) saturate(160%);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
  box-shadow: var(--shadow-md);
}

.stats-list li {
  margin: 0;
  text-align: center;
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  padding: 0.4rem;
  border-radius: var(--radius-md);
  transition: background var(--transition), transform var(--transition);
}

.stats-list li:hover {
  background: rgba(255, 122, 69, 0.08);
  transform: translateY(-3px);
}

.stats-list .num {
  font-size: clamp(1.6rem, 4vw, 2.4rem);
  font-weight: 900;
  line-height: 1.1;
  background: var(--grad-accent);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.stats-list li > span:last-child {
  font-size: 0.88rem;
  color: var(--text-soft);
}

/* ============ About ============ */
#about {
  background: var(--bg-alt);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  margin-top: 1rem;
  margin-bottom: 1rem;
}

#about h3 {
  color: var(--orange-deep);
  margin-top: 1.6rem;
  padding-left: 0.85rem;
  border-left: 4px solid var(--orange);
}

#about h3:first-of-type { margin-top: 0; }

/* ============ Products ============ */
#products h3 {
  padding: 1.1rem 1.3rem 0.5rem;
  margin: 0;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-bottom: none;
  border-radius: var(--radius-md) var(--radius-md) 0 0;
  color: var(--orange-deep);
  transition: background var(--transition), box-shadow var(--transition);
}

#products h3 + p {
  margin: 0 0 1.2rem;
  padding: 0.3rem 1.3rem 1.1rem;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-top: none;
  border-radius: 0 0 var(--radius-md) var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition), transform var(--transition);
}

#products h3:hover + p {
  box-shadow: var(--shadow-md);
}

#products ul {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 0.8rem;
  list-style: none;
  padding: 0;
  margin-top: 1.4rem;
}

#products ul li {
  margin: 0;
  padding: 1rem 1.1rem;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: var(--shadow-sm);
  color: var(--text-soft);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

#products ul li:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--orange);
}

/* ============ Solutions ============ */
#solutions {
  background: var(--grad-soft);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
}

#solutions h3 {
  color: var(--orange-deep);
  margin-top: 1.4rem;
}

#solutions h3:first-of-type { margin-top: 0; }

#solutions p {
  padding-left: 1rem;
  border-left: 3px solid rgba(255, 122, 69, 0.28);
  transition: border-color var(--transition);
}

#solutions p:hover { border-color: var(--orange); }

/* ============ Cases ============ */
#cases h3 {
  margin-top: 1.6rem;
  color: var(--text);
}

#cases h3:first-of-type { margin-top: 0; }

#cases blockquote {
  background: var(--bg-alt);
  border-left-color: var(--orange);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition);
}

#cases blockquote:hover {
  transform: translateX(4px);
  box-shadow: var(--shadow-md);
}

/* ============ News & Articles 卡片 ============ */
#news,
#articles {
  display: block;
}

#news article,
#articles article {
  position: relative;
  padding: 1.3rem 1.4rem;
  margin-bottom: 1rem;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
  overflow: hidden;
}

#news article::before,
#articles article::before {
  content: "";
  position: absolute;
  top: 0; left: 0;
  width: 4px; height: 100%;
  background: var(--grad-accent);
  transform: scaleY(0);
  transform-origin: top;
  transition: transform var(--transition);
}

#news article:hover,
#articles article:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--orange);
}

#news article:hover::before,
#articles article:hover::before { transform: scaleY(1); }

#news article h3,
#articles article h3 {
  margin-bottom: 0.35rem;
  font-size: 1.08rem;
}

#news article p,
#articles article p { margin-bottom: 0.6rem; }

#news article a,
#articles article a {
  font-weight: 700;
  font-size: 0.88rem;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
}

#news article a::after,
#articles article a::after {
  content: "→";
  transition: transform var(--transition);
}

#news article a:hover::after,
#articles article a:hover::after { transform: translateX(4px); }

/* 文章列表网格 */
#articles {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1rem;
  align-items: start;
}

#articles > h2 {
  grid-column: 1 / -1;
  margin-bottom: 0.6rem;
}

#articles article { margin-bottom: 0; }

/* ============ FAQ ============ */
#faq details {
  margin-bottom: 0.7rem;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: box-shadow var(--transition), border-color var(--transition);
}

#faq details[open] {
  border-color: var(--orange);
  box-shadow: var(--shadow-md);
}

#faq summary {
  cursor: pointer;
  padding: 1rem 2.6rem 1rem 1.2rem;
  font-weight: 700;
  color: var(--text);
  list-style: none;
  position: relative;
  transition: background var(--transition), color var(--transition);
}

#faq summary::-webkit-details-marker { display: none; }

#faq summary::after {
  content: "+";
  position: absolute;
  right: 1.1rem;
  top: 50%;
  transform: translateY(-50%);
  font-size: 1.3rem;
  font-weight: 400;
  color: var(--orange);
  transition: transform var(--transition);
}

#faq details[open] summary::after { transform: translateY(-50%) rotate(45deg); }

#faq summary:hover { background: rgba(255, 122, 69, 0.07); }

#faq details p {
  margin: 0;
  padding: 0 1.2rem 1.1rem;
  animation: fadeDown 0.35s ease both;
}

@keyframes fadeDown {
  from { opacity: 0; transform: translateY(-6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ============ HowTo ============ */
#howto {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}

#howto h3 {
  color: var(--orange-deep);
  margin-top: 1.5rem;
}

#howto h3:first-of-type { margin-top: 0; }

#howto ol {
  counter-reset: step;
  list-style: none;
  padding: 0;
}

#howto ol li {
  counter-increment: step;
  position: relative;
  padding: 0.75rem 1rem 0.75rem 3rem;
  margin-bottom: 0.6rem;
  background: var(--bg-soft);
  border-radius: var(--radius-md);
  transition: transform var(--transition), box-shadow var(--transition);
}

#howto ol li::before {
  content: counter(step);
  position: absolute;
  left: 0.8rem;
  top: 50%;
  transform: translateY(-50%);
  width: 1.7rem; height: 1.7rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.85rem;
  font-weight: 800;
  color: #fff;
  background: var(--grad-accent);
  border-radius: 50%;
}

#howto ol li:hover {
  transform: translateX(4px);
  box-shadow: var(--shadow-sm);
}

#howto ul li::marker { color: var(--orange); }

/* ============ Contact ============ */
#contact address {
  padding: 1.4rem 1.5rem;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  box-shadow: var(--shadow-sm);
  margin-bottom: 1.4rem;
}

#contact address p { margin-bottom: 0.5rem; }
#contact address p:last-child { margin-bottom: 0; }

#contact h3 { color: var(--orange-deep); }

/* ============ Sitemap & Links ============ */
#sitemap ul,
#links ul {
  list-style: none;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}

#sitemap li,
#links li { margin: 0; }

#sitemap a,
#links a {
  display: inline-block;
  padding: 0.42em 1em;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-soft);
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  transition: color var(--transition), background var(--transition), border-color var(--transition), transform var(--transition);
}

#sitemap a:hover,
#links a:hover {
  color: #fff;
  background: var(--grad-accent);
  border-color: transparent;
  transform: translateY(-2px);
  text-decoration: none;
}

/* ============ Privacy & Disclaimer ============ */
#privacy,
#disclaimer {
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
}

#privacy p,
#disclaimer p { margin-bottom: 0; }

/* ============ Footer ============ */
#site-footer {
  margin-top: 2rem;
  background: var(--bg-alt);
  border-top: 1px solid var(--border);
  padding: 2.4rem 1.2rem 3.4rem;
}

.footer-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  text-align: center;
}

.footer-inner p {
  font-size: 0.86rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}

.footer-inner p:first-child {
  font-weight: 700;
  color: var(--text-soft);
}

.footer-inner nav ul {
  list-style: none;
  padding: 0;
  margin: 1rem 0 0;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1.2rem;
}

.footer-inner nav li { margin: 0; }

.footer-inner nav a {
  font-size: 0.86rem;
  font-weight: 600;
  color: var(--text-soft);
}

.footer-inner nav a:hover { color: var(--orange); }

/* ============ Back to top ============ */
#back-to-top {
  position: fixed;
  right: 1.2rem;
  bottom: 1.4rem;
  z-index: 90;
  padding: 0.6em 1.1em;
  font-size: 0.82rem;
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px);
  transition: opacity var(--transition), visibility var(--transition), transform var(--transition), box-shadow var(--transition);
}

#back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

/* ============ 响应式 ============ */
@media (max-width: 1024px) {
  .header-inner { gap: 0.7rem; }
  #main-nav ul { gap: 0; }
  #main-nav a { padding: 0.35em 0.55em; font-size: 0.86rem; }
  #site-search input { width: 120px; }
}

@media (max-width: 860px) {
  .header-inner {
    flex-wrap: nowrap;
    justify-content: space-between;
  }

  #menu-toggle { display: inline-flex; }

  #main-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex: 0 0 100%;
    background: var(--glass-bg);
    backdrop-filter: blur(20px) saturate(160%);
    -webkit-backdrop-filter: blur(20px) saturate(160%);
    border-bottom: 1px solid var(--glass-border);
    box-shadow: var(--shadow-md);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s cubic-bezier(0.22, 0.61, 0.36, 1);
  }

  #main-nav.open { max-height: 520px; overflow-y: auto; }

  #main-nav ul {
    flex-direction: column;
    padding: 0.6rem;
    gap: 0.15rem;
  }

  #main-nav a {
    padding: 0.7em 1em;
    font-size: 0.94rem;
    border-radius: var(--radius-sm);
  }

  .header-tools { flex-wrap: nowrap; }
  #site-search input { width: 110px; }

  .stats-list { grid-template-columns: repeat(2, 1fr); }

  #articles { grid-template-columns: 1fr; }

  .hero-slider { min-height: auto; }
}

@media (max-width: 600px) {
  body { font-size: 15px; }

  .header-inner {
    padding: 0.6rem 0.9rem;
    gap: 0.5rem;
  }

  .brand { font-size: 1rem; }
  .brand svg { width: 32px; height: 32px; }

  #site-search { display: none; }

  #theme-toggle,
  #menu-toggle {
    padding: 0.45em 0.8em;
    font-size: 0.78rem;
  }

  #hero { padding: 2rem 0.9rem 1.4rem; }

  .slide { padding: 1.2rem 1.1rem; border-radius: var(--radius-md); }

  .slide p { font-size: 0.92rem; }

  .slider-controls { justify-content: center; }

  .breadcrumb { padding: 0 0.9rem; }

  main > section { padding: 2.2rem 0.9rem; }

  #stats { padding: 0 0.9rem 1.6rem; margin-top: -1.2rem; }

  .stats-list { padding: 1rem 0.7rem; gap: 0.6rem; }

  .stats-list li > span:last-child { font-size: 0.8rem; }

  #products ul { grid-template-columns: 1fr; }

  #products h3,
  #products h3 + p { padding-left: 1rem; padding-right: 1rem; }

  #news article,
  #articles article { padding: 1.1rem 1.1rem; }

  #faq summary { padding: 0.9rem 2.4rem 0.9rem 1rem; font-size: 0.95rem; }

  #howto ol li { padding-left: 2.7rem; }

  #back-to-top {
    right: 0.8rem;
    bottom: 0.9rem;
    padding: 0.55em 0.9em;
    font-size: 0.78rem;
  }

  #site-footer { padding: 2rem 0.9rem 3rem; }
}

@media (max-width: 380px) {
  .stats-list { grid-template-columns: 1fr; }
  .brand-name { display: none; }
}

/* ============ 减少动效偏好 ============ */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }

  main > section {
    opacity: 1;
    transform: none;
  }
}

/* ============ 打印 ============ */
@media print {
  #site-header,
  #back-to-top,
  .slider-controls,
  .header-tools { display: none !important; }

  body { background: #fff; color: #000; }

  main > section { opacity: 1; transform: none; page-break-inside: avoid; }
}